1. Field of the Invention
The present invention relates to a gas amount measurement device. More specifically, the present invention relates to a gas amount measurement device for measuring an entire amount of gas contained in molten metal or an amount of gas attached to an inclusion.
2. Description of the Related Art
Conventionally, a specific metal or alloy is used for a component such as a vehicle engine. Meanwhile, it is generally known that an amount of impurity gas per unit weight after refining a component is smaller than that before refining. This is because the impurity gas contained in a sample, that is, the component vaporizes during refining. In such a case, the refined component is molten again so as to reduce the amount of impurity gas in the component as much as possible. However, the melting of the refined component again undesirably causes a cost hike.
Furthermore, recycling has recently become popular for used metal products from the viewpoint of effective use of resources. However, if an aluminum product, for example, is melted, various types of gases such as hydrogen gas, carbon dioxide gas, oxygen gas, and nitrogen gas are released. Due to this, if the used aluminum product is cast in a mold, bubbles disadvantageously remain in an obtained product and pinholes or the like undesirably occur in the obtained product.
To solve these problems, it is proposed to measure a gas amount in molten metal. A measurement device including a chamber containing the molten metal, a pump setting an internal pressure of the chamber to a predetermined pressure, and a measuring unit measuring the internal pressure of the chamber, and measuring a gas amount from a pressure rise due to gas released from the molten metal is disclosed in, for example, Jpn. Pat. Appln. KOKAI Publication No. 2003-83865.
However, with the technique disclosed in Jpn. Pat. Appln. KOKAI Publication No. 2003-83865, the measurement device can only measure the total amount of all the gases present, but not individual gases.